As part of a project to perform successful laser angioplasty, it is necessary to develop a swine colony with severe atherosclerotic vascular lesions within six months. The acceleration is obtained by balloon endothelian denudation of carotid and femoal arteries after which the animals are placed on a cholesterol-laden, high fat diet. Development of vascular lesions will be assessed by ultrasonic, nuclear, and angiographic methods. Animals with severe lesions will be used for the angioscopy and laser angioplasty studies.